/Engine/Plugins/Experimental/Gauntlet/Source/Gauntlet/Public/GauntletTestController.h
In essence your derived class should implement logic that starts and monitors a test, then calls EndTest(Result) when the desired criteria are met (or not!)
[UCLASS](Programming/UnrealArchitecture/Reference/Classes#classdeclaration)() class UGauntletTestController : public [UObject](API\Runtime\CoreUObject\UObject\UObject)